385257217 has 4 divisors (see below), whose sum is σ = 385339140. Its totient is φ = 385175296.

The previous prime is 385257211. The next prime is 385257221. The reversal of 385257217 is 712752583.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 214066161 + 171191056 = 14631^2 + 13084^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-385257217 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 385257217.

It is not an unprimeable number, because it can be changed into a prime (385257211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33448 + ... + 43465.

It is an arithmetic number, because the mean of its divisors is an integer number (96334785).

Almost surely, 2^385257217 is an apocalyptic number.

It is an amenable number.

385257217 is a deficient number, since it is larger than the sum of its proper divisors (81923).

385257217 is an equidigital number, since it uses as much as digits as its factorization.

385257217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81922.

The product of its digits is 117600, while the sum is 40.

The square root of 385257217 is about 19627.9702720378. The cubic root of 385257217 is about 727.6406073606.

The spelling of 385257217 in words is "three hundred eighty-five million, two hundred fifty-seven thousand, two hundred seventeen".